- 10 - 



One of the outstanding features of Alar is its consistent abil- 

 ity to prevent preharvest drop. Even at the reduced concentrations 

 used in this study, drop control was excellent (Table 2). 



Table 2. Effect of Alar on the preharvest drop of 'Mcintosh' apples 



Alar 



treatment (ppm) 



Total 

 yield ( b u . ) 



Total 

 drop (bu . ) 



Preharvest 

 Drop (%) 



A. 



B. 500 



C. 750 



D. 1000 



102 

 125 

 133 

 120 



40.3 

 8.1 

 4.7 

 5.7 



39.4 

 6.5 

 3.7 



4.9 



1 



Six trees per treatment, applied August 7 



Alar, while controlling drop at these lower concentrations also 

 had an effect on fruit firmness (Table 3.). 



Table 3. Effect of Alar on flesh firmness of 'Mcintosh' apples. 



Alar treatment (ppm) 



Firmness (lbs.) 



A. 



B. 500 



C. 750 



D. 1000 



11 .9 

 14.7 

 14.8 

 15.4 



1 



Six trees per treatment, applied August 7. 

 "Average firmness of 10 apples per tree 4 days after harvest. 



Summary 



Increased yearly use of Alar by commercial f 

 create problems related to carry-over effects. R 

 tions, if effective, may minimize these problems, 

 that 500, 750 and 1000 ppm provided good drop con 

 ober 4 and delayed fruit flesh softening. The co 

 be able to use Alar at concentrations of 500-750 

 acre) on at least a part of his orchard and thus 

 hazards and costs involved in using this growth r 

 by Southwick and Lord (1) showed, however, that 1 

 may be required for suitable drop control for per 

 the present study (2 weeks). 



Literature Cited 



ruit growers may 

 educed concentra- 



This study showed 

 trol through Oct- 

 mmercial grower may 

 ppm (2-3 pounds per 

 reduce the possible 

 etardant. Findings 

 000-2000 ppm Alar 

 iods longer than in 



Southwick, F.W., and W.J. Lord. 1970. Some seasonal and residual 

 responses of Mcintosh apples to successive annual applications of 

 Alar. 76th Ann. Meeting Mass. Fruit Growers Assoc . 76:110-119. 



